How do I calculate a combined median of two groups

[ablackburn]

I have two groups of data that I want to calculate the combined median for.One group has 4,094 sales with a median of $573,139 and the 2nd group is 1,259 sales with a median of $2,023,814.How do I calculate the median of the combined groups?Thanks

 

[Eric W]

You need to calculate the median from the combined group, you can't do it from the medians and sizes of the groups.

	A	B	C
1	1		10
2	2		10
3	3		10
4	4		11
5	5		12
6	6		12
7	7		12
8
9	4		11
10		8.5

<colgroup><col style="width: 25pxpx"><col><col><col></colgroup><thead>
</thead><tbody>
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Sheet2​

Worksheet Formulas Cell Formula A9 =MEDIAN(A1:A7) C9 =MEDIAN(C1:C7) B10 =MEDIAN(A1:A7,C1:C7) <thead> </thead><tbody> </tbody>

<tbody>
</tbody>

 

[Rick Rothstein]

I have two groups of data that I want to calculate the combined median for.One group has 4,094 sales with a median of $573,139 and the 2nd group is 1,259 sales with a median of $2,023,814.How do I calculate the median of the combined groups?Thanks

Eric has told you how to do what you asked for; but, if the values you posted are representative in any way, I have to wonder of what use such a number would be. The median is the value in the middle of the set. Given the large difference in sales between the two groups, the median of the combined groups will always come from the group with the larger number of sales... the only thing the smaller sales group will do is pull the median from a different location within that larger sales group. Since the medians between the two groups is so widely different, I cannot see what value there would be in obtaining the median for the combined groups. Are you sure you mean the median and not the mean (average)?

 

[ablackburn]

Unfortunately, the groups are summed, so I don't have the sale prices of the individual sales. I just have the numbers above, so I don't think the formula from Eric will work.

 

[Eric W]

If the numbers you gave are the means (NOT medians) of the groups, you can calculate the mean of both combined groups like this:

=(573139*4094+2023814*1259)/(4094+1259)

However, if those are medians, then this will generate some meaningless number you should not use for anything. Depending on what you're trying to achieve, you may not have enough information to make a good decision. The answer would be to get more information, not try to torture the information you have into giving you something that doesn't work.

What are you trying to achieve?